日志重定向

背景: 第三方调试日志，需要真实路测场景 或者 提供完整的日志 给与排查。
就是这么简单。通过pp助手之类查看doucment文档目录

- (void)redirectNSLogToDucumentFile{
    //创建文件路径
    NSString *documentpath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
    NSDate *currentDate = [NSDate date];
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
    NSString *currentDateString = [dateFormatter stringFromDate:currentDate];
    NSString *fileName = [NSString stringWithFormat:@"log_%@.txt",currentDateString];
    NSString *logFilePath = [documentpath stringByAppendingPathComponent:fileName];
    //删除已经存在文件
    NSFileManager *fileManager = [NSFileManager defaultManager];
    [fileManager removeItemAtPath:logFilePath error:nil];
      // 将log输入到文件
    freopen([logFilePath cStringUsingEncoding:NSASCIIStringEncoding], "a+", stdout);
    freopen([logFilePath cStringUsingEncoding:NSASCIIStringEncoding], "a+", stderr);
}

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    [self redirectNSLogToDucumentFile];
}